Jaspers, a German psychiatrist, published General Psychopathology in 1913. Jaspers, Schneider, and Mayer-Gross were members of the Heidelberg school. General Psychopathology, indirectly through Schneider’s and Mayer-Gross’ textbooks and directly by its English translation in 1963, led to a narrow set of schizophrenia criteria in the United Kingdom. General Psychopathology had very limited direct impact on US psychiatry, which adopted a broader schizophrenia definition. The difference between UK and US schizophrenia was a key element in the Diagnostic and Statistical Manual of Mental Disorders, Third Edition, and the neo-Kraepelinian revolution. General Psychopathology contains two essential interrelated ideas: a) psychiatry is a hybrid scientific discipline that must combine natural and social science methods that provide an explanation of illness that follows the medical model and an understanding of psychiatric abnormalities that are variations of human living, respectively, and b) psychiatric disorders are heterogeneous. Berrios’ ideas on the hybridity of psychiatry in the United Kingdom and McHugh’s ideas on psychiatric diagnoses in the United States can be considered neo-Jasperian approaches because they further elaborate these two Jasperian concepts in the late 20th century.